RESUMEN
BACKGROUND: Bell's palsy is a peripheral paralysis of the seventh cranial nerve, whose etiology is unknown. Using polymerase chain reaction technology, it is possible to sample accessible body fluids and identify possible viral factors. The purpose of this research is to investigate its connection to the herpes virus family by testing for the presence of the virus in the saliva and tear fluid of Bell's palsy patients. METHODS: Saliva and tears were collected from 42 children and adolescents suffering from idiopathic facial nerve paralysis. Polymerase chain reaction was used to test for the presence of the viruses Epstein-Barr virus, cytomegalovirus, herpes simplex virus 1 and 2, varicella zoster virus and human herpes virus 6 (HHV-6). Samples were also taken from a control group without paralysis. A second specimen was taken from patients who tested positive for HHV-6 several months after their recovery. RESULTS: Of the 42 patients in the study group, 71% (30 patients) tested positive for HHV-6, compared with only 37% of the control group (P = 0.001). The prevalence of the other 5 viruses tested was low-herpes simplex virus 1: 9.5%, Epstein-Barr virus: 9.5%, cytomegalovirus: 4.8%, varicella zoster virus: 2.3% and herpes simplex virus 2: 0%. Twenty-four of the 30 patients who were HHV-6-positive during their illness were reexamined following recovery. Only 13 patients (54.2%) excreted the virus after recovery from the paralysis. CONCLUSIONS: Herpes 6 virus appears to play some role in the etiology of facial nerve paralysis. The virus was detected in the saliva of children during acute illness and decreased with resolution. Our research opens new insights linking HHV-6 to the etiology of Bell's palsy in children.